1. 10 Nov, 2007 2 commits
    • Stephen Hemminger's avatar
      sky2: enable PCI config writes · ac93a394
      Stephen Hemminger authored
      On some boards, PCI configuration space access is turned off by default.
      The 2.6.24 driver doesn't turn it on, and should have.
      Signed-off-by: default avatarStephen Hemminger <shemminger@linux-foundation.org>
      Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
      ac93a394
    • David Miller's avatar
      [FUTEX] Fix address computation in compat code. · 3c5fd9c7
      David Miller authored
      compat_exit_robust_list() computes a pointer to the
      futex entry in userspace as follows:
      
      	(void __user *)entry + futex_offset
      
      'entry' is a 'struct robust_list __user *', and
      'futex_offset' is a 'compat_long_t' (typically a 's32').
      
      Things explode if the 32-bit sign bit is set in futex_offset.
      
      Type promotion sign extends futex_offset to a 64-bit value before
      adding it to 'entry'.
      
      This triggered a problem on sparc64 running 32-bit applications which
      would lock up a cpu looping forever in the fault handling for the
      userspace load in handle_futex_death().
      
      Compat userspace runs with address masking (wherein the cpu zeros out
      the top 32-bits of every effective address given to a memory operation
      instruction) so the sparc64 fault handler accounts for this by
      zero'ing out the top 32-bits of the fault address too.
      
      Since the kernel properly uses the compat_uptr interfaces, kernel side
      accesses to compat userspace work too since they will only use
      addresses with the top 32-bit clear.
      
      Because of this compat futex layer bug we get into the following loop
      when executing the get_user() load near the top of handle_futex_death():
      
      1) load from address '0xfffffffff7f16bd8', FAULT
      2) fault handler clears upper 32-bits, processes fault
         for address '0xf7f16bd8' which succeeds
      3) goto #1
      
      I want to thank Bernd Zeimetz, Josip Rodin, and Fabio Massimo Di Nitto
      for their tireless efforts helping me track down this bug.
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3c5fd9c7
  2. 09 Nov, 2007 38 commits